1. Field of the Invention
The present invention relates to a probe card, in particular, to a probe card having a helical contactor.
2. Description of the Related Art
Generally, in order to detect a defect in semiconductor components such as integrated circuits (ICs) and large scale integrated circuits (LSIs), probe cards are commonly used.
When a semiconductor component formed on a wafer is examined by using a common probe card to examine whether it is defective or not, in order to conduct a continuity test, numerous contactors of the probe card are positioned so that the contactors can contact corresponding electrodes of the semiconductor component formed on the wafer. The contactors are provided on a surface of a base wiring layer (or a rewiring layer if the rewiring layer is disposed on the base wiring layer) of the probe card. The types of contactors provided on a probe card can be broadly divided into two types.
A first-type contactor is a needle-type contactor that is composed of a needle (probe pin) with a spring at the bottom end thereof, and this type has been widely used. The use of this probe pin is advantageous in that the length of movement of the probe pin can be easily increased. However, in consideration of high density arrangement of electrodes introduced by miniaturization of semiconductors, it is difficult to realize a high density arrangement of probe pins with a pitch of 150 μm or less because the density of a probe pin array is limited by the shape and structure of the probe pins. Furthermore, it is difficult to improve performance of a contactor in a high-frequency region because the length of movement of a probe pin is long.
In order to satisfy such a requirement of a high-density array or a high performance of contactors in a high-frequency region of contactors, a second-type contactor 104 provided on a known probe card 101 shown in FIG. 7 has been used. The second-type contactor 104, which is provided on a surface 103a of a rewiring layer 103 laminated on a base wiring layer 102 constituting the probe card 101, is made of a thin-film wire formed in a helical shape so as to function as a spring.
However, since it is difficult to form the second-type helical contactor 104 having a large height, the second-type contactor 104 cannot have a greater range of movement than that of the first-type contactor formed in a needle shape. Therefore, if a semiconductor wafer (hereinafter simply referred to as wafer) 110 contacts the probe card 101 at an angle, as shown in FIG. 8, the semiconductor component fails to contact only the contactor 104 and faultily contacts a non-contactor area CB, which is an area having no contactors, of the base wiring layer 102 or the rewiring layer 103. Accordingly the wafer 110 including the semiconductor component becomes damaged.
Furthermore, as shown in FIG. 9, since the second-type contactor 104 has a diameter of about 100 μm and a height of about 50 μm, if the flatness of a contactor area CA, which is an area having contactors, of the base wiring layer 102 or the rewiring layer 103 is as large as about 25 μm to 30 μm, each second-type contactor 104 becomes significantly tilted according to the flatness of contactor area CA around each contactor. Therefore, when a wafer 110 is placed so that electrodes thereon contact all the second-type contactors 104 provided at an angle, the wafer 110 may also contact the area CB of the base wiring layer 102 or the rewiring layer 103, and in such a case, the wafer 110 becomes damaged as mentioned above.
In consideration of the above, the present invention provides a probe card which can prevent damages caused by contact of a wafer and the area where the contactors are not formed.